SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'ceb99cf83138b1908379085a62309ef29b1d57b28ad654fd61128f6d032ba553' 
  AND token = 'LMQC6UDTAKaYDkOchuoqvXh3WOXCvSwZEPPW64yvVBc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00035

JSON explain

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