SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '5603de4548242c7c6b5d081f9e45272710b1d4124232cdae07a1a46d233d11a4' 
  AND token = 'yjyNkKbYAspi1T8wA4ZETAsCsCw3oLeRKCmCJ7yXdu8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00042

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}