SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'e13642853889d75ae6f0269f21916ea25d6e613201346100df19465dc80c1fac' 
  AND token = 'g+f0bv49SCu9iScLHxBwqA2BE7xloDOAqzmVy/Njspg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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