SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '175dc1f858c98bc8c8491bc11717a901b1216ea21c22d4c8a937b3846f4b43fb' 
  AND token = '+NhostGF/RKl9fXfpOwnugQ/6EHmQGNESZjWaBqey3c=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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