SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'f5e1af5c1747d373cdf80483f76356870013cf3aa3eb50b8f66f5d01ececf518' 
  AND token = 'Tdh9Pz0On9JOP9wnwEvfPo3YpedaArNyl6wTW5uffC4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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