SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'a55603a4b00979999dbd72591b79f95937c091ce415e8ed2c7c1705f2211c674' 
  AND token = 'Oatp3GwzMLSP0UQJzf/RXvi3x/o/VjDCjU+bYWL56Pw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00043

JSON explain

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