SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '6ee199497b3f9099277cffe60840b6f5bae90a0f40af4e443d757518b4001120' 
  AND token = 'JnLda7Z87OJ6q+SefjrULkxuTWjkffGhhRKyuxab0Fc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00038

JSON explain

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