SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '9dcc80eefdc5b405d248c87e0d2ade312c338b7949814618dab9bdd94348a0f9' 
  AND token = 'p0AMw8Qy/umHhQ8qM/CitrURqZDBSbs0JO1wxNRDatg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00024

JSON explain

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