SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'fd633ba8bed72a3977d8906328883789c99eac596da2f76a3824ab523e4c4ef7' 
  AND token = 'kFg7Ru5BaYPDucEuTGs7wylB8K7crbVxt7l+2j4eulk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00027

JSON explain

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