SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = 'fd4b7b1a2906cab3e0b26c385425c9078e60906e6cd029930f55f58ae00109fa' 
  AND token = 'D+vPPvolFacRCIJAhwNJXAuV84An+r10xgNwaWvYf0Y=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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