SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'd629391054c55de2d09dd7c6fbf89f456a83b3ea408e68aabfabc458dfeab22f' 
  AND token = 'lQIeIKC47E9MbXIB3K4W5egB3/OUtSUfkNl7hyMBOkU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00038

JSON explain

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