SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'eebf081355963c2bf65a47dcf520fc48e98befd1c2a0ce19bae5e4fe08c90055' 
  AND token = 'XRwwdvlTEor6kesp/vOp3ECaq98Rsl1MObFsb1tyhok=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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