SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '622fa63595dabbe58c4678714f60104d2621e554a39a0434466f538b31ac0071' 
  AND token = 'ke2DTnMm0Nl7o9rhMpZUMdc2cLYYAgwCMNxXj2Tyt9o=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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