SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = 'c83186b5f5df0e1d6fe524bdecb277a956353183b53ad1f538d742b00a86d0eb' 
  AND token = 'h02SfM+qaVMdcC3iLDPGNtgeG0E0Mt8j0y1pAq90NEA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00039

JSON explain

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