SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '23667eba36f072431a80af03663391463096ad85a8ce88b2111a8e2e12c8eaf5' 
  AND token = 'MulPwUzBHiL3ARBRtm2KyKLn4bloaXKk4/EYpMdbBnE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00034

JSON explain

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