SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ccadf7a927f97df282607c7c21a1bf5bf27eefb1892c94684b05df051df8e3da' 
  AND token = '08b4kyJvRh53BhdDnxjseWmg+fw9BuM7VFIZGirL1Jw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00018

JSON explain

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