SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'a7c948509ba450397c354f62cee4e59302c5fa3f8e1ba249b1b6779fc7485d7a' 
  AND token = 'MHP7Twjc9mSTxUFLP/roqQcrPgqkB83cMDC6sFn5eJc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00042

JSON explain

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