SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '67408c0983e7e876b2c62c6d23e6f221ab4d1152d51de084c0350830b4e1ff95' 
  AND token = 'sjeGehCSiJaVLXVxic8hqLx4Mt8QmmeC7JHu0W5tep0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00045

JSON explain

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