SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '963504952ba1bdd2b14f9ff583cb2c1288f8037d817da6421f5a95109fa137b1' 
  AND token = 'dDnOW3jAHCkJTHLtMCS3jWPdcRkzLDsO422eUPMMcRg=' 
  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"
    }
  }
}