SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '967650cf2c2a1e8aa4d382367691c0b986040134d3acd095d79a33f323e10018' 
  AND token = 'nJ5Btm8D8ZD7Duq4nlN3PBV0OHzJvrRy0LcLIbe/asE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00038

JSON explain

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