SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '693e3579ede7e1e18d57cf2a5ef35df4da7835935632228b33cbc784b7f81d38' 
  AND token = 'nr66rlgGQ8ExrkdSTJ8vyxoNHP0D9R2hAe7m7bn35sk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00044

JSON explain

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