SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '179f4d209b133ce2a7d3537c09674c4b301da66fd8ddd0fce90f1c6e3e3b0898' 
  AND token = 'nUqjZS0nFnDM56mIVHIn1w1OnPqsmQUft3mf2U0aAxc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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