SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'f2c1d0c40b3ad7823777ba07eacb5734ac061ad63c31f48af8f0eb94026b5620' 
  AND token = 'h+72/oBY1QoHMEagFhjjVPHrjTe7JiRgQ9wlzEBAk2w=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00042

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}