SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'bfef86b1438b6c794c2b7862c9800e3c2f7e16ae5a6fa886b31fecf87495cf87' 
  AND token = 'ChILLVy7eZ07QtKuUw/ZBFtY/UfyniXUPiCFrbZz/Uk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00024

JSON explain

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