SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '6e165e3d1d8409a02f8b3b54ad4500f242af22c42b3f9784d39c1a7bcae551a5' 
  AND token = 'WTZ3aoEoTWgUtgHkTXnlKlz5OPEaj6uwszLZr+3uddI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}