SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'c2f68910b64870c4a3bac697df1eb2e9224d6d234a24c5c4db3f1c6b7889630c' 
  AND token = 'e/V1WwqD8v3FJWwbRDmcX9odLqmspztFtwL+o9YAJfo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

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