SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '099f8c702a0d8213c15de6bd9869ac16bd5497439b50ce34c3327390f2a7e020' 
  AND token = 'ZG1DM7wtx/189pqy+11KyTLMiprf8whRCTzmu/gsLpY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

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