SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '4990fac737d4ec6a04b606104bea0ebb91610bd7f8156f69f803b1b37e882887' 
  AND token = '1zF2ThzeoHLdTV/XEwAU1n+iyDY5uOkEB/B6xJTV+EM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00041

JSON explain

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