SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '35ac99f3f5ad59e1359443b61eb40d2f5e23f020c40e2d5a21764f4d91aa2f3c' 
  AND token = 'PMGq5kojj9PjANJsJEjwxrdJ9/HlJDZ11lzQ+BfiPXE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00046

JSON explain

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