SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = '3158276a002b44de32cd9fa20083d47e4305ea2ad1802541b68a5088e2884cfb' 
  AND token = 'JtrdjVFONgF3zhqUGRTywqv4qNAU7cwYOlrluRmCR84=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00036

JSON explain

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