SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '3b82164e510351ff578450976221e23407474fe1d06cd1d68669ffabd7759b28' 
  AND token = 'xK5z/a7055CljUeEsc5XmHsWdAF7Erobl9qAQ8O/6lQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00040

JSON explain

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