SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'fdd12cec3c9a8595c21eeee09d2176d1255217ac4f03a92678ad8168acdc23e3' 
  AND token = 'bIBAQN2aV6tpaYglNJV9PfU3k+jax0bzSS7rnEdXVUg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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