SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'eeb389d3da031481520f87be534569ffd5c122c8369705e8d30be87032c37eb2' 
  AND token = 'T23fmEkrsyLSrp4xWCAHHU5Z43EQpNE9Lw76m9alfL0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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