SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'c6f7863760cb458a8828717c0e893ac03caa8fa7d470fb86cec6277d191778c9' 
  AND token = 'XeJiz2i07bu/qwAr/rwCxlTpfT9NfPxiNaUuvQdSq8Y=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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