SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'd1eb2ef0d61f32b9061ec7d278a15adeed9271719c73ac3144e116adc27b764a' 
  AND token = 'zXvNoEAobJ3qyowuibXc4kVBjva498490Dt8MgZRdJk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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