SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'e9ba295643a7593bc622e77e42f2b3886e17a6eaf271a8f50246385ac5fff949' 
  AND token = 'eI3r+MAf0vKyIKsRUJ/LSBJs5uRGP3Ur4tlh3/zAI60=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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