SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '272006edc3c97e54bc83e41851dcf6504d1a241ac4ce18e44e15ac8140bb151b' 
  AND token = 'dErzqb1+9ERgb+AJMeuyU+zPujpyMWF0xhkl0sPWMjc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00024

JSON explain

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