SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'e3cd39f2ba6822332b581c6f3246bf5592672323ec027f13258e51e69671f5bb' 
  AND token = 'NadVL63ac8m8rwcNlo6JdTb8HB49mrUgEASRrDAkMew=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00036

JSON explain

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