SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'd787115691f1b637df6e197947f0452384279f903cd7797dd365a1f892b9ac5c' 
  AND token = 'rz5bMlxD917C3LYrTJXza/zilLFOZD5bxj4zO/iwpqI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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