SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '9fc8f2109544cf17e835e2848d01be63377d370053deef540527ccb0cd2f6f98' 
  AND token = 'grNyfwTvRuL6lDq1yddYn4u1d3ESZhQIMePQaaiiY5Y=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00036

JSON explain

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