SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'f8b0b4d83ef8dcbf1180126340a2f12e418ae7d134125b8c1744141a54fc1a88' 
  AND token = 'b1SZHtVFOeOzPFtpmnjCYk6TUWWmCE1ciz1YvUutLn0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00048

JSON explain

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