SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'a0e1b9f0a4417278992e6432ffd59c38feae19b0f53402b6bca96f14be0a07ad' 
  AND token = 'TAuagT1YV1TpvdyHi7bE0z05/y4O9xRMktXcikqck8g=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00041

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}