SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '578433e0071c19af1e2b14af48594390831d037588c2fee07c1dfa9f9ab80987' 
  AND token = 'uThxDv6xrsMGQaF1g8nnrdUDyaw/2WWbeXk87TjohSo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00039

JSON explain

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