SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'ce1cafc4f0af797b9036a7203cfe4d694df03c2348da63650c99d73bbe962777' 
  AND token = '+NaocVI2us6JUOK70xQUutp7DmcIzgbfJ0C7qYp8OJE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00037

JSON explain

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