SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'e6303b6c0556ce257418b95bd48bfd23d1c2e3ad6171d61d44609883887667b9' 
  AND token = '1aguhMPW6aKMUmtDjKCFSY04wFax3GOHjgpFyCtaFY0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00052

JSON explain

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