SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'da25949846de7e6e1bdff9887380547ab9e2a5779a0509d113d11ff7b83fd872' 
  AND token = 'Tw12szQyrPMCbo09TzKorKK+HCx05LVdsAhW89nYC6s=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00039

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}