SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '4a882f6904624373b102e84baa120a9d044ca7db1897ee678b09595c7ae57970' 
  AND token = 'MMLF/SrKgAaauPj2PunDz3neNktVDF9lmg5eU4uRPFE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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