SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ba101b2087b21ac64e08fc68bab357c985d15f2cc589f541ed53e461dc469d90' 
  AND token = 'pfG2++JBXGRLMXtQwkzNdTPCm8G4M/ouynKq8BjDVmk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00020

JSON explain

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