SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '52fc3c4412da740a3ee4f9c2be07def7841a3a0261e11be9b6a8eba2b1220f27' 
  AND token = 'qbL1XhuZ5uV9kQTv9wzfeKa22J50LUAE5T5vSMYktag=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00037

JSON explain

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