SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'dcfc19b0ac343c1c305c0c9b45876cc20571110bb17458bee146102737495a82' 
  AND token = 'NYIrP+Tg87haLSfvSjTfwXyQb+A8Bl36wDZnQxZEYj8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

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