SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '10707d37535fe1a5cccef4c30436a2680d8a517244e4051829c547cd36527eb4' 
  AND token = 'dg3nwzuiMTWao7JIffdTSbPtliGDmKBTN8fhylhAFug=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00045

JSON explain

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