SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'e2689c0ed662c57fbf934783bba6b0eab97f6cebca1e47abe72c06af51c182d5' 
  AND token = 'y0FAlArTOqX7ocDGhwcC/MpYKZdgOhmdrN1LEjK+l/I=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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