SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '58fe992b0ed30bec51d52ee1cb543f4ff13abb89ae8522d6252226e45f2b7e01' 
  AND token = 'WETSjNJFDPVDgm+Lqu3gx45QwTbmvOHBF7p6T3b+1DM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00020

JSON explain

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