SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '705d7e37141281b48aa7efab56fc057d7a8d2297d85be2b2e637d26fe3190bb4' 
  AND token = 'T6yGYaebpk3n0CXTiStnBJ8x5inthBTYmR2HbfSnt5g=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}